The thickness of R38 batt insulation is usually about 12 inches. This substantial thickness helps to provide excellent thermal resistance, making it a popular choice for insulating attics and other areas where maintaining a high level of energy efficiency is crucial.
The main difference is in installation; batt insulation comes in pre-cut pieces, while roll insulation is installed by rolling it out between ceiling joists.
Drying time for wet insulation depends on type, ventilation, temperature, and humidity. If it doesn't dry within 2-3 days, it should be removed to prevent mold and wood decay.